Check for integer rounding?

[AnotherUser]

Hi,

I recently had an integer rounding bug, where the result was always zero, as floating point should have been used for the intermediate calculation involving non-constant variables. Cppcheck (git 524828a...) did not warn me about this. Is this implemented?

{

    int i,j,k;
    i = 9;
    j = 10;
    k = 5;

    cerr << (i-j)/k << endl;

}

[Daniel Marjamäki]

there is no warning for such code.

people often use integer division by intention.

we don't want to warn when the result is truncated by intention. that would be a false positive.

how could we see that the truncation is unintentional?

[AnotherUser]

how could we see that the truncation is unintentional?

I didn't show it in my example, but in my case (and in the comment), all the variables were const - it is highly unlikely that a zero value would be expected from a const calculation where all the values are obtained from local variables.